Objectives: Growth impairment in children with Betathalassemiamajor (BTM) has several possible etiologiesincluding excess iron overload and endocrinologic abnormalities.We aimed to assess growth in children withBTM and its relation with serum ferritin, thyroid hormones,IGF1 and IGFBP3.Materials and methods: Thirty-three children with BTMand 30 healthy children (control group) matched in age,sex and height were subjected to full clinical history andexamination, including anthropometric measurements.Fasting blood samples from both groups were taken forcomplete blood counts, fasting blood sugar, liver functiontests, serum ferritin, thyroid profiles, IGF1 and IGFBP3.Bone ages for both groups were determined radiologically.Results: A total of 57.6% of BTM group had retardedlinear growth and 45.5% of them were with delayed puberty.There was statistical significant decrease in upper/lower segment (U/L) ratio in the BTM group comparedto the control group (p=0.035). No apparent hypothyroidismwas found in the thalassemia group, but significantdecreases were found in both IGF1 and IGFBP3 levels ofthe thalassemia group compared with the control group(p=0.022 and p=0.037, respectively). There was a significantcorrelation between T4 and U/L ratio (p<0.05); IGF1was significantly correlated with height, duration of transfusionsand duration of chelation (p<0.05). No significantcorrelation was found between serum ferritin and othervariables of the patients.Conclusions: Growth retardation in children with BTM isevident despite regular transfusions and chelation therapy,especially in children with older age and the cause ismainly in growth hormone-IGF1 and IGFBP3 axis. J ClinExp Invest 2012; 3(2): 157-163